<template>
  <div>
    <!-- 面包屑导航区域 -->
    <el-breadcrumb separator-class="el-icon-arrow-right">
        <el-breadcrumb-item :to="{ path: '/home' }">首页</el-breadcrumb-item>
        <el-breadcrumb-item>商品管理</el-breadcrumb-item>
        <el-breadcrumb-item>参数列表</el-breadcrumb-item>
    </el-breadcrumb>

    <!-- 卡片视图区域 -->
    <el-card>
        <!-- 警告区域 -->
        <el-alert
            title="注意:只允许为第三级分类设置相关参数!"
            type="warning"
            :closable="false"
            show-icon
        >
        </el-alert>

        <!-- 选择商品分类区域 -->
        <el-row class="cat_opt">
            <el-col>
                <span>选择商品分类:</span>
                <!-- 选择商品分类的级联选择框 -->
                <el-cascader
                    v-model="selectedCateKeys"
                    :options="catelist"
                    :props="cateProps"
                    @change="handleChange"
                    clearable
                >
                </el-cascader>
            </el-col>
        </el-row>
        <!-- tab 页签区域 -->
        <el-tabs v-model="activeName" @tab-click="handleTabClick">
            <!-- 添加动态参数的面板 -->
            <el-tab-pane label="动态参数" name="many">
                <!-- 添加参数的按钮 -->
                <el-button type="primary" size="mini" :disabled="isBtnDisabled" @click="addDialogVisible = true">添加参数</el-button>
                <!-- 动态参数表格 -->
                <el-table :data="manyTableData" border stripe>
                    <!-- 展开行 -->
                    <el-table-column type="expand">
                        <template v-slot="scope">
                            <!-- 循环渲染tag标签 -->
                            <el-tag v-for="(item,i) in scope.row.attr_vals" :key="i" closable @close="handleClose(i,scope.row)">{{item}}</el-tag>
                            <!-- 输入的文本框 -->
                            <el-input
                                class="input-new-tag"
                                v-if="scope.row.inputVisible"
                                v-model="scope.row.inputValue"
                                ref="saveTagInput"
                                size="small"
                                @keyup.enter.native="handleInputConfirm(scope.row)"
                                @blur="handleInputConfirm(scope.row)"
                            >
                            </el-input>
                            <!-- 添加按钮 -->
                            <el-button v-else class="button-new-tag" size="small" @click="showInput(scope.row)">+ New Tag</el-button>
                        </template>
                    </el-table-column>
                    <!-- 索引列 -->
                    <el-table-column type="index"></el-table-column>
                    <el-table-column label="参数名称" prop="attr_name"></el-table-column>
                    <el-table-column label="操作">
                        <template v-slot="scope">
                            <el-button size="mini" type="primary" icon="el-icon-edit" @click="showEditDialog(scope.row.attr_id)">编辑</el-button>
                            <el-button size="mini" type="danger" icon="el-icon-delete" @click="removeParams(scope.row.attr_id)">删除</el-button>
                        </template>
                    </el-table-column>
                </el-table>
            </el-tab-pane>
            <!-- 添加静态属性的面板 -->
            <el-tab-pane label="静态属性" name="only">
                <!-- 添加属性的按钮 -->
                <el-button type="primary" size="mini" :disabled="isBtnDisabled" @click="addDialogVisible = true">添加属性</el-button>
                <!-- 静态属性表格 -->
                <el-table :data="onlyTableData" border stripe>
                    <!-- 展开行 -->
                     <el-table-column type="expand">
                        <template v-slot="scope">
                            <!-- 循环渲染tag标签 -->
                            <el-tag v-for="(item,i) in scope.row.attr_vals" :key="i" closable @close="handleClose(i,scope.row)">{{item}}</el-tag>
                            <!-- 输入的文本框 -->
                            <el-input
                                class="input-new-tag"
                                v-if="scope.row.inputVisible"
                                v-model="scope.row.inputValue"
                                ref="saveTagInput"
                                size="small"
                                @keyup.enter.native="handleInputConfirm(scope.row)"
                                @blur="handleInputConfirm(scope.row)"
                            >
                            </el-input>
                            <!-- 添加按钮 -->
                            <el-button v-else class="button-new-tag" size="small" @click="showInput(scope.row)">+ New Tag</el-button>
                        </template>
                    </el-table-column>
                    <!-- 索引列 -->
                    <el-table-column type="index"></el-table-column>
                    <el-table-column label="属性 名称" prop="attr_name"></el-table-column>
                    <el-table-column label="操作">
                        <template v-slot="scope">
                            <el-button size="mini" type="primary" icon="el-icon-edit" @click="showEditDialog(scope.row.attr_id)">编辑</el-button>
                            <el-button size="mini" type="danger" icon="el-icon-delete" @click="removeParams(scope.row.attr_id)">删除</el-button>
                        </template>
                    </el-table-column>
                </el-table>
            </el-tab-pane>
        </el-tabs>
    </el-card>

    <!-- 添加参数的对话框 -->
    <el-dialog
        :title="this.activeName === 'many' ? '添加动态参数' : '添加静态属性'"
        :visible.sync="addDialogVisible"
        width="50%"
        @close="addDialogClosed"
    >
        <!-- 添加参数的对话框 -->
        <el-form :model="addForm" :rules="addFormRules" ref="addFormRef" label-width="100px">
            <el-form-item :label="this.activeName === 'many' ? '动态参数' : '静态属性'" prop="attr_name">
                <el-input v-model="addForm.attr_name"></el-input>
            </el-form-item>
        </el-form>
        <span slot="footer" class="dialog-footer">
            <el-button @click="addDialogVisible = false">取 消</el-button>
            <el-button type="primary" @click="addParams">确 定</el-button>
        </span>
    </el-dialog>

    <!-- 修改参数的对话框 -->
    <el-dialog
        :title="this.activeName === 'many' ? '修改动态参数' : '修改静态属性'"
        :visible.sync="editDialogVisible"
        width="50%"
        @close="editDialogClosed"
    >
    <!-- 修改参数的对话框 -->
        <el-form :model="editForm" :rules="editFormRules" ref="editFormRef" label-width="100px">
            <el-form-item :label="this.activeName === 'many' ? '动态参数' : '静态属性'" prop="attr_name">
                <el-input v-model="editForm.attr_name"></el-input>
            </el-form-item>
        </el-form>
        <span slot="footer" class="dialog-footer">
            <el-button @click="editDialogVisible = false">取 消</el-button>
            <el-button type="primary" @click="editParams">确 定</el-button>
        </span>
    </el-dialog>
  </div>
</template>

<script>
export default {
    data(){
        return {
            //商品分类列表
            catelist:[],
            //级联选择框的配置对象
            cateProps:{
                expandTrigger: 'hover',
                value:'cat_id',
                label:'cat_name',
                children:'children'
            },
            //级联选择框双向绑定到的数组
            selectedCateKeys:[],      
            //被激活的页签的名称
            activeName:'many',
            //动态参数数据
            manyTableData:[],
            //静态参数数据
            onlyTableData:[],
            //控制添加对话框的显示与隐藏
            addDialogVisible:false,
            //添加参数的表单数据对象
            addForm:{
                attr_name:''
            },
            //添加表单的验证规则对象
            addFormRules:{
                attr_name:[{
                    required:true,
                    message:'请输入参数名称',
                    trigger:'blur'
                }]
            },
            //控制修改对话框的显示与隐藏
            editDialogVisible:false,
            //修改的表单数据对象
            editForm:{},
            //修改表单的验证规则对象
            editFormRules:{
                attr_name:[{
                    required:true,
                    message:'请输入参数名称',
                    trigger:'blur'
                }]
            }
        }
    },
    created(){
        this.getCateList()
    },
    methods:{
        async getCateList(){
            const {data : res} = await this.$http.get('categories')
            if(res.meta.status !== 200){
                return this.$message.error('获取商品分类失败！')
            }
            this.catelist = res.data
        },
        //级联选择框选中项变化，会触发这个函数
        handleChange(){
            this.getParamsData()
        },
        // tab 页签点击事件的处理函数
        handleTabClick(){
            this.getParamsData()
        },
        //获取参数的列表数据
        async getParamsData(){
            if(this.selectedCateKeys.length === 3){
                //根据所选分类的Id，和当前所处的面板，获取对应的参数
                const {data : res } = await this.$http.get(`categories/${this.cateId}/attributes`,{
                    params:{sel:this.activeName}
                })

                if(res.meta.status !== 200){
                    return this.$message.error('获取参数列表失败')
                }

                res.data.forEach(item => {  //循环将每一个参数中attr_val字符串转化为数组
                    item.attr_vals = item.attr_vals ? item.attr_vals.split(' ') : []
                    //控制文本框的显示与隐藏
                    item.inputVisible = false
                    //文本框中输入的值
                    item.inputValue = ''
                })
                
                if(this.activeName === 'many'){
                    this.manyTableData = res.data
                } else {
                    this.onlyTableData = res.data
                }
            }else{
                this.selectedCateKeys = []
                this.manyTableData = []
                this.onlyTableData = []
                return
            }
        },
        //监听添加对话框的关闭事件
        addDialogClosed(){
            this.$refs.addFormRef.resetFields()
        },
        // 点击按钮，添加参数
        addParams(){
            this.$refs.addFormRef.validate(async valid => {
                if(!valid){
                    return;
                }
                const {data : res} = await this.$http.post(`categories/${this.cateId}/attributes`,{
                    attr_name:this.addForm.attr_name,
                    attr_sel:this.activeName
                })

                if(res.meta.status !== 201){
                    return this.$message,error('添加参数失败！')
                }

                this.$message.success('添加参数成功!')
                this.addDialogVisible = false
                this.getParamsData()
            })
        },
        //点击按钮，展示修改的对话框
        async showEditDialog(attr_id){
            //查询当前参数的信息
            const {data : res} = await this.$http.get(`categories/${this.cateId}/attributes/${attr_id}`,{
                params:{
                   attr_sel:this.activeName 
                }
            })
            if(res.meta.status !== 200){
                return this.$message.error('获取参数信息失败！')
            }
            this.editForm = res.data
            this.editDialogVisible = true
        },
        //重置修改的表单
        editDialogClosed(){
            this.$refs.editFormRef.resetFields()
        },
        //点击按钮，修改参数信息
        editParams(){
            this.$refs.editFormRef.validate(async valid =>{
                if(!valid)return;
                const {data : res} = await this.$http.put(`categories/${this.cateId}/attributes/${this.editForm.attr_id}`,{
                    attr_name:this.editForm.attr_name,
                    attr_sel:this.activeName
                })
                if(res.meta.status !== 200){
                    return this.$message.error('修改参数失败！')
                }
                this.$message.success('修改参数成功！')
                this.getParamsData()
                this.editDialogVisible = false
            })
        },
        //根据id删除对应的参数项
        async removeParams(attr_id){
            const confirnResult = await this.$confirm('此操作将永久删除该参数, 是否继续?', '提示', {
                confirmButtonText: '确定',
                cancelButtonText: '取消',
                type: 'warning'
            }).catch(err => err)

            //用户取消了删除的操作
            if(confirnResult !== 'confirm'){
                return this.$message.info('已取消删除！')
            }

            //删除的业务逻辑
            const {data : res} = await this.$http.delete(`categories/${this.cateId}/attributes/${attr_id}`)

            console.log(res)
            if(res.meta.status !== 200){
                return this.$message.error('删除参数失败！')
            }

            this.$message.success('删除参数成功!')
            this.getParamsData()
        },
        //文本框失去焦点,或摁下了 Enter 键都会触发
        async handleInputConfirm(row){
            if(row.inputValue.trim().length === 0){
                row.inputValue = ''
                row.inputVisible = false
                return
            }
            //如果没有return，则证明输入的内容，需要做后续处理
            row.attr_vals.push(row.inputValue.trim())
            row.inputValue = ''
            row.inputVisible = false
            //需要发送请求，保存这次操作
            this.saveAttrVals(row)
        },
        //将对 attr_vals 的操作，保存到数据库
        async saveAttrVals(row){
             //需要发送请求，保存这次操作
            const {data : res} = await this.$http.put(`categories/${this.cateId}/attributes/${row.attr_id}`,{
                attr_name:row.attr_name,
                attr_sel:row.attr_sel,
                attr_vals:row.attr_vals.join(' ')
            })

            if(res.meta.status !== 200){
                return this.$message.error('修改参数项失败！')
            }

            this.$message.success('修改参数项成功！')
        },
        //点击按钮，展示文本输入框
        showInput(row){
            row.inputVisible = true
            //让文本框自动获得焦点
            //$nextTick 方法的作用就是当页面上元素被重新渲染之后，才会执行回调函数中的代码
            this.$nextTick(_ => {
                this.$refs.saveTagInput.$refs.input.focus();
            });
        },
        //删除对应的参数可选项
        handleClose(i,row){
            row.attr_vals.splice(i,1)
            this.saveAttrVals(row)
        }
    },
    computed:{
        //如果按钮需要被禁用，则返回true，否则返回false
        isBtnDisabled(){
            if(this.selectedCateKeys.length !== 3){
                return true
            }
            return false
        },
        //当前选中的三级分类的Id
        cateId(){
            if(this.selectedCateKeys.length === 3){
                return this.selectedCateKeys[2]
            }
            return null
        }
    }
}
</script>

<style lang="less" scoped>
.cat_opt{
    margin:15px 0;
}
.el-tag{
    margin:10px;
}
.input-new-tag{
    width:120px;
}
.el-cascader{
    margin-left: 10px;
}
</style>